Proportional fluid distribution assembly for back hoe having reciprocating teeth

ABSTRACT

A back hoe apparatus including an articulated boom having a bucket affixed to one end of the boom, and hydraulic power fluid conveying lines extending along the boom to the bucket. Mounted in the bottom of the bucket are a hydraulic motor, a plurality of reciprocably mounted teeth, and means drivingly interconnecting the motor and the teeth. A fluid distribution assembly is provided between a source of hydraulic fluid and the hydraulic motor for the purpose of proportionately distributing hydraulic power fluid to the hydraulic motor to drive the teeth in reciprocation, and the hydraulic cylinder employed to roll or pivot the bucket about the end of the articulated boom upon which it is mounted. The fluid distribution assembly may be generally described as including three major subassemblies; a solenoid valve, an adapter block and a flow divider block.

United States Patent [191 Fleming [451 Aug. 13, 1974 [76] Inventor: Ancel H. Fleming, 3715 Tulsa,

Oklahoma City, Okla. 731 12 [22] Filed: Feb. 15, 1973 [21] Appl. No.: 332,727

[52] US. Cl. 214/138 R, 37/141 T, 37/DIG. 18, 60/422, 60/484, 91/411 R, 137/101, 137/599, 299/37 [51] Int. Cl E021 3/32 [58] Field of Search 37/D1G. 18, 141, 142; 60/422, 484; 137/101, 118, 625.48, 599, 599.1; 91/411 R; 299/14, 37; 214/138 [56] References Cited UNITED STATES PATENTS 3,123,089 3/1964 Thrap et a1. 137/101 3,436,849 4/1969 Haynes 37/141 R 3,448,535 6/1969 Haynes 37/141 R 3,543,646 12/1970 lijima 60/422 X 3,703,186 11/1972 Brewer 137/101 Primary Examiner-Robert E. Pulfrey Assistant Examiner-Clifford D. Crowder Attorney, Agent, or Firm-Dunlap, Laney, Hessin, Dougherty & Codding 5 7] ABSTRACT A back hoe apparatus including an articulated boom having a bucket affixed to one end of the boom, and hydraulic power fluid conveying lines extending along the boom to the bucket. Mounted in the bottom of the bucket are a hydraulic motor, a plurality of reciprocably mounted teeth, and means drivingly interconnecting the motor and the teeth. A fluid distribution assembly is provided between a source of hydraulic fluid and the hydraulic motor for the purpose of proportionately distributing hydraulic power fluid to the hydraulic motor to drive the teeth in reciprocation, and the hydraulic cylinder employed to roll or pivot the bucket about the end of the articulated boom upon which it is mounted. The fluid distribution assembly may be generally described as including three major subassemblies; a solenoid valve, an adapter block and a flow divider block.

5 Claims, 10 Drawing Figures PATENTEBAUEI 3mm SHEET 2 OF 2 All BACKGROUND OF THE INVENTION 1. Related Prior Patents This application contains subject matter which is related to the subject matter set forth in US. Pat. Nos. 3,436,849 and 3,448,535 issued June 10, 1969 to Freddie J. Haynes. The foregoing patents both relate to a back hoe apparatus having movable teeth.

2. Field of the Invention This invention relates to earth excavating apparatus, and more particularly, to back hoes of the type having movable teeth which can be moved in reciprocation to enhance the digging effectiveness of the apparatus.

3. Brief Description of the Prior Art In US. Pat. No. 3,448,535, there is described a back hoe apparatus having movable teeth, which teeth are driven by an improved drive assembly which includes a hydraulic motor which drives in rotation, a cam shaft carrying a plurality of lobes which bear against cooperating surfaces of rods which are secured to the teeth so that the teeth are driven in reciprocation, and in out-ofphase relationship with each other. The described apparatus, and the improved drive system which is provided, affords a very effective digging action through the vibration of the teeth, and constitutes an improvement over standard back hoes as previously constructed.

BRIEF DESCRIPTION OF THE PRESENT INVENTION The present invention provides an improvement in back hoe structures of the type having driven movable teeth, such as the back hoe structure described in US. Pat. No. 3,448,535. Broadly described, the improvement in such back hoe structures, as constituted by the present invention, comprises a hydraulic power fluid distribution assembly which permits selective distribution of hydraulic power fluid to the teeth when the teeth are to be driven in reciprocation, and to a hydraulic cylinder utilized to rotate or roll the bucket of the back hoe about its pivotal axis on the end of the articulated boom of the back hoe. The power fluid proportioning and distribution assembly of the invention broadly includes an electric solenoid valve which may be selectively shifted to either of two alternate positions, an adapter block secured to the solenoid valve for transferring and receiving power fluid therefrom, and a flow divider block secured to the opposite side of the adapter block from the solenoid valve and adapted to proportionately divide power fluid being directed to the hydraulic motor used for the purpose of driving the teeth of the back hoe in reciprocation, and to the piston and cylinder used for rolling or pivoting the bucket about its pivotal axis at the end of the articulated boom. The improvement preferably further includes an electrical push button switch connected to the electrical solenoid valve and mounted on a hand lever forming an operator for a main on-off valve interposed in the hydraulic power fluid line extending from a source of power fluid to the power fluid distribution assembly of the invention.

By the use of the described improvement, the operator can selectively control the amount of power fluid which is directed to the reciprocable teeth of the back hoe or, alternatively, to the piston and cylinder used to roll or pivot the bucket on the end of the articulated boom, depending upon the type of digging or excavation which is being undertaken.

The improvement of the present invention further includes a protective flexible sleeve positioned around the reciprocating rods to which the back hoe digger teeth are secured, and function to prevent any dirt or deleterious material from contacting and adhering to these teeth.

An important object of the invention is to provide an improvement in back hoe structures which improves the flexibility or versatility of such structures in excavating various types of soils and terrains.

Another object of the invention is to provide an improvement in back hoe structures of the type having reciprocating teeth mounted on the leading edge of the back hoe bucket, which improvement facilitates the use of the existing hydraulic system on back hoes for the adaptation of the back hoes to the inclusion of such reciprocating teeth thereon.

An additional object of the invention is to provide better control to the operator of a back hoe having reciprocating teeth mounted on the bucket thereof so that the operator can more effectively use the hoe for digging either hard or soft soils, and for obtaining maximum penetration in minimum time.

Additional objects and advantages of the invention will become apparent as the following detailed description of a preferred embodiment of the invention is read in conjunction with the accompanying drawings which illustrate the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view of a back hoe apparatus constructed in accordance with the present invention.

FIG. 2 is a side view, partly in section and partly in elevation, of a typical back hoe bucket having reciprocating teeth mounted thereon, in combination with which the present invention is utilized.

FIG. 3 is a sectional view through the forward and lower portion of the bucket, showing the manner in which the teeth are mounted thereon, and in which a hydraulic motor is mounted in the bucket for driving the teeth in reciprocation.

FIG. 4 is a plan view of one of the reciprocating teeth used at the leading side of the back hoe bucket and illustrating a protective sylphon sleeve employed in combination with the tooth.

FIG. 5 is a side elevation view of the power fluid distribution assembly constituting a salient feature of the present invention.

FIG. 6 is a perspective view of an adapter block forming a part of the power distribution assembly, as such adapter block appears when viewed from one side thereof.

FIG. 7 is a perspective view of the adapter block shown in FIG. 6 and portraying the appearance of the other side of the adapter block from that which is shown in FIG. 6.

FIG. 8 is a perspective view of a flow divider block forming a part of the fluid distribution assembly of the invention.

FIG. 9 is a sectional view taken through the center of the flow divider block.

FIG. is a schematic flow diagram illustrating the path of flow of hydraulic power fluid in the system which includes the invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION Referring to the drawings in detail, and particularly to FIG. 1, reference numeral 10 designates generally a self-propelled vehicle of the type conventionally employed in back hoe devices. The self-propelled vehicle 10 has secured to the rear end thereof, an articulated boom structure which includes a first boom member 14 and a second boom member 16. The second boom member 16 is pivotally connected to the first boom member 14 and its movement is controlled by a suitable hydraulic cylinder 18 and piston rod 20 which are controlled by a suitable hydraulic control system located on the vehicle 10, and partially described hereinafter. The first member 14 is pivotally secured to the vehicle, and its movement is controlled by means of a suitable cylinder 24 and piston rod 26.

A bucket 28 is pivotally connected to the free outer end of the member 16 by means of a universal hitch connection 30. The universal hitch connection 30 is preferable to the type described in Haynes US. Pat. No. 3,448,5 35, and is constructed to permit the bucket 28 to be pivoted on the end of the boom member 16 about a pivot pin 31. The bucket 28 is of conventional shape, and thus includes substantially parallel side walls 32, a dirt carrying bottom wall 34 and an arcuate or curved back wall 36 which is preferably formed integrally with the bottom wall 34. The bucket 28 is actuated in its rolling pivotal movement about the horizontal axis formed by the pivot pin 3] by reciprocating a piston rod 44 by means of a suitable hydraulic cylinder 52.

The bucket 28 further includes (in addition to the side walls 32, the dirt carrying bottom wall 34 and the arcuate or curved back wall 36), a lower chamber wall 54 which, with the bottom wall 34 and the lower portions of the side walls 32, forms an open receiving chamber 56 which is open at its front end and at its rear end. A removable arcuate closure plate 58 is constructed with a curvature and transverse dimension which permit it to be fitted in the lower portion of the bucket 28 in the manner best depicted in FIG. 2. Thus, the arcuate closure plate 58 has its forward edge 58a secured to the rear edge of the lower chamber wall 54 and has its rear edge 58b secured to the lower edge of the back wall 36 of the bucket.

Positioned within the open chamber 56 is a removable sealed driving unit designated generally by reference numeral 60. The sealed driving unit includes a casting block 62 which is an integrally cast element constructed to accommodate a prime mover or driving unit, drive rods connected to the digging teeth, and a cam shaft, all of which are more specifically described hereinafter. Thus, the casting block 62 has a transversely extending well 64 formed in the rear portion thereof, and defined by a pair of side walls 66 and a rear wall 68. Positioned within the well 64 is a hydraulic motor 70 which has a pair of rigid conduits 72 and 74 extending to and through the rear wall 68 for conveying hydraulic power fluid to and away from the motor. The conduits 72 and 74 extend through apertures and sealing elements in the rear wall 68 of the casting block, and take-up nuts or fittings 76 are tightened on the conduits to draw the motor firmly against the rear wall of the casting block. Flexible power fluid conduits 80 and 82 are connected to the rigid conduits 72 and 74, respectively, for conveying power fluid to and from these conduits.

Along its central portion, the casting block 62 is built up to provide a transversely extending cam shaft housing 84. The housing 84 has a bore 85 extending therethrough from one side of the casting block 62 to the other, and this bore receives an elongated, generally cylindrical cam shaft 86. The cam shaft 86 is described in US. Pat. No. 3,448,535 hereinbefore cited, and is used for the purpose of driving in reciprocation, a plurality of digger teeth 90 through the intervening instrumentality of a plurality of rods 92. The manner in which the cam shaft 86 is driven in rotation by the hydraulic motor 70 through a suitable chain 94, and the manner in which the cam shaft cooperates with the beveled ended rods 92 for driving the teeth 90 in reciprocation are also described in Haynes US. Pat. No. 3,448,535, and that description and the teachings of that patent are incorporated herein by reference.

At the front edge of the bucket 28, a front plate 93 closes the housing 56 and has its edges secured to the bottom wall 34 and the lower chamber wall 54. The

front plate 93 is provided with a plurality of holes therethrough which receive bushings 94. Each of the bushings 94 surrounds, and slidably receives, one of the rods or shafts 92 which has at the outer end thereof,

one of the reciprocably mounted digger teeth 90.

Adjacent each tooth 90 in a close fitting relationship surrounding the respective rod is a circumferentially grooved annular collar 95. A grooved hub 96 is provided on the bushing 94 outside the housing 56 in opposed relationship to the circumferentially grooved collar 95. A flexible protective sleeve 97, which may be constructed of rubber or similar material, surrounds each of the rods 92 at that portion of the respective rod which projects forwardly from the bucket 28 and carries the digger tooth 90 at the end thereof. The flexible sleeve 97 has beads 97a and 97b formed at opposite ends thereof, and these beads are annular in configuration and dimensioned to facilitate their engagement with the annular grooves formed in the collar and the hub 96, respectively. The length of the flexible sleeve 97 is such that it may be extended without stressing or distortion to the position depicted in FIG. 4 when the tooth 90 adjacent which it is located has been reciprocated to its fully extended position. When the respective tooth 90 is retracted during its reciprocating stroke, the flexible sleeve 97 is compressed and deformed in the manner illustrated in FIG. 3. The flexible sleeve 97 functions to protect the otherwise exposed portions of the rods 92 from contact with dirt and abrasive material, and prevents such material from working between the rods and the bushings 94 in which the rods are slidably mounted.

Hydraulic fluid supplying the cylinders 18, 52 and 24 is supplied via a series of control valves 99 mounted adjacent the operator seat on the vehicle 10. The valves 99 function cooperatively with the flow divider and distribution assembly of the invention in a manner hereinafter described.

The fluid flow divider and distribution assembly forming a portion of the present invention, and consti tuting a salient aspect thereof, is illustrated in detail in FIGS. 5-9 and its function is illustrated schematically in FIG. 10. The fluid flow proportioning and distribution system is designated generally by reference numeral 100, and includes a two position electrical solenoid valve 102, an adapter block 104, and a flow divider block 106. The adapter block 104 is shown in detail in FIGS. 6 and 7 which portray this sub-assembly as it appears when viewed from two opposite perspective viewpoints. The adapter block 104 is a solid metallic block which has a top face 104a, a bottom face 104!) and side faces 104a and 104d. The adapter block also has fastener securement holes 108, 110, 112 and 114 bored through the block near the four corners thereof to facilitate securement of the block to the solenoid valve and to the fluid flow divider block 106.

A plurality of bores are formed in the adapter block 104 and extend substantially horizontally with respect to the two opposed substantially parallel, monoplanar major faces 104a and 1041) thereof. These bores are shown in dashed lines in the drawings, and are designated by reference numerals 118, 120, 122 and 124. The bore 118 is entered through a port 126 in one side wall or face 104d of the adapter block 104, with the port 126 functioning to receive power fluid from a hydraulic pump 127 (illustrated schematically in FIG. provided as a conventional structure in back hoe construction. It may be added that the flexible conduit or fluid flow line which extends from the hydraulic pump to the port 126 in the present invention isthat which normally extends from this pump to the valves 99 used for controlling the flow of power fluid to the cylinders 18, 24 and 52. The bore 118 further communicates with a bore 128 which extends normal thereto and opens in the top face 104a of the adapter block 104. At the opening of the bore 128 in the top face 104a of the block 104, a fluid port 130 is formed, and communicates with a port of opening formed in an abutting flat surface of the solenoid valve 102 when the solenoid valve is secured to the adapter block 104 in the manner depicted in FIG. 5.

The bore 120 opens into the side face 104d of the adapter block 104, and at this point is internally threaded to form a port 132. The port 132 is threadedly connected to a conduit which extends to the conventional power fluid reservoir, and forms a fluid return line which functions to return power fluid to the reservoir when a pressure relief valve located in the com mercially available two-way solenoid valve 102 functions. Communication with the interior of the two-way solenoid valve 102 is provided via a bore 134 which intersects the bore 120 at a right angle, and opens in the top face 1040 of the adapter block 104.

The bore 122 formed in the adapter block 104 is plugged by a suitable plug 138 at the side face 1040 of the block 104, but communicates with a pair of bores 140 and 142 which open in the top face 104a and the bottom face 104!) of the block 104, respectively. The bore 142 opens into the lower face 104b of the block 104 at a port 144 which registers and communicates with a port 146 formed in the flow divider block 106 (see FIG. 8) secured to the lower or under side 1041) of the adapter block 104, and on the opposite side thereof from the electrical solenoid valve 102. The bore 140 which intersects the bore 122 terminates in the top face 104a of the adapter block 104 in a port 148 which registers with a port or opening formed in the face of the solenoid valve 102 which flatly abuts the upper face of the adapter block 104, and which forms 6 an opening into the interior passageways within the valve.

A bore 124 opens in the side face 1046 of the adapter block 104, and the opening of the bore is threaded to form a port to which is connected a suitable conduit leading to, and supplying power fluid to, the control valves 99 located at the operators console. The bore.124 is intersected within the body of the adapter block 104 by a bore 150 which extends upwardly to the face 104a of the adapter block 104, and by a bore 152 which extends downwardly to the face 104b of the adapter block 104. The bore 152 terminates at the face 10417 in an opening 156 which is superimposed over, and in registry with an opening or port 158 formed in the face of the flow divider block 106 which abuts the face 104b of the adapter block 104. The bore 150 which projects upwardly from the bore 124 to the face 104a of the adapter block 104 terminates in this face in an opening 160, which opening registers with an opening formed in the bottom face of the solenoid valve 102.

The flow divider block 106 which is secured to the lower side or face 104]) of the adapter block 104 is of generally right parallepiped configuration, and is preferably formed of a solid body of metal. A plurality of bores are formed in the flow divider block 106, and extend in a substantially horizontal direction or, more accurately described, extend substantially parallel to the two opposed major planes forming the top face and bottom face of the flow divider block. The top face is that face which is flatly abutted against the face l04b of the adapter block 104. In FIG. 9 of the drawings, a sectional view taken through the center of the flow divider block 106 has been illustrated, and shows the several bores or internal passageways which are formed therein.

A flow divider device which can be modified for use in the combination of the present invention is commerically available from Brand Hydraulics, Inc. of Omaha, Nebraska, and is one of the F G-Series sold by that company. The divider is adapted to provide a constant governed flow from one of the discharge ports thereof, so that if the input of hydraulic fluid to the flow divider increases, all of the increase will pass out through a second discharge port, and will not affect the governed discharge. The governed flow which is obtainable is adjustable in such a flow divider over a range of 95 percent of the total input. Both the governed outlet and the by-pass outlet are pressure compensated, and can be used without affecting each other.

To more clearly illustrate the structural modifications made to the flow divider block 106 in incorporating it in the combination of the present invention, reference is made to FIGS. 8 and 9 of the drawings. The port 146, which has been heretofore referred to as located in the face of the flow divider block 106 which is adjacent the adapter block 104, opens into a downwardly extending passageway 171. The passageway 171 opens into a bore 172 which is closed by a suitable plug 173. The bore 172 communicates with a fluid delivery passageway 174 into which an adjusting screw 176 extends. The adjusting screw 176 functions to permit adjustment of the percentage of the input flow which will be delivered to one of the outlet ports in the flow divider block for ultimate delivery to the motor 70 as hereinafter explained.

An elongated bore 177 is formed transversely through the flow divider block 106 and is closed at its opposite ends by a pair of pipe plugs 178 and 179. Disposed within the bore 177 is a metering spool 180 which is shiftable in the bore in response to the internal pressure of hydraulic power fluid acting thereon. Theshifting of the metering spool 180 accomplishes the metering of the hydraulic power fluid so that a preselected constant volume of the power fluid passes into a passageway 182, and the remainder of the power fluid passes into a passageway 184. The constant volume of the hydraulic power fluid delivered to the passageway 182 is dependent upon the setting of the adjusting screw 176.

Extending across the flow divider block 106 substantially parallel to the bore 177 is an elongated bore 185 which intersects the passageways 182 and 184, and is closed at one of its ends by a pipe plug 188. A bore 189 which extends to the top face of the flow divider block 106 intersects the bore 185 near the plug 188 and terminates in the port 158 which is aligned with the port opening into the bore 152 in the adapter block 104 as hereinbefore explained. At the end of the elongated bore 185 opposite its end which is closed by the pipe plug 188, the bore opens at a port 192 formed in the side of the flow divider block 106. A suitable conduit (not shown) is provided for conveying hydraulic power fluid from the port 192 to the hydraulic motor 70 which is used to drive the teeth of the back hoe bucket in reciprocation as hereinbefore described.

A spring loaded pressure relief valve 194 is positioned in the bore 185 and includes a spring 194a which bears against an adjusting screw 196 threaded in this bore, and a ball 19412 which is biased by the spring against a check seat 198 also threaded into the bore at the opposite end thereof. A tank port 200 is provided in one side of the divider block 106 and communicates through a passageway with a central portion of the bore OPERATION The operation of the hydraulic power fluid distribution assembly of the present invention, in conjunction with the back hoe apparatus in which it is used, occurs at a time when the back hoe bucket 28 is being employed for excavating, and the teeth are intermittently actuated to enhance the penetrating power of the bucket in hard soils. As with a conventionally operated back hoe, the articulated boom can be manipulated in several ways, such as by pivotally elevating the first boom member 14, or by pivoting the second boom member 16 upon the end of the first boom member so as to move the bucket 28 toward and away from the vehicle which carries the back hoe structure, or both the first boom member 14 and the second boom member 16 may be actuated concurrently. It is also possible, by the use of the hydraulic cylinder 52 and piston 44, to cause the bucket 28 to be rolled or pivoted about the pivotal axis constituted by the pin 31 so that a scraping or scooping motion is imparted to the bucket. Control of these motions through the several hydraulic cylinders described is effected by means of the control valves 99 provided on a control console adjacent the operators seat.

The hydraulic power fluid for supplying each of the hydraulic cylinders used to impart the described motions to the articulated boom structure and to the back hoe is developed by hydraulic power fluid stored in a reservoir (see FIG. 10) and delivered by a suitable hydraulic pump 127 through suitable flexible hoses and conduits via the hydraulic power fluid distribution assembly of the invention. A suitable push button switch 210 may be mounted on or adjacent the console which carries the control valves 99, and this switch functions to actuate the two position electrical solenoid valve 102 hereinbefore identified at times and for purposes hereinafter described.

As previously explained, the two position electrical solenoid valve 102, in one of its operating positions, shifts to a position such that hydraulic power fluid from the conventional hydraulic pump is divided within the power fluid distribution system of the invention, and a predetermined constant volume of the hydraulic power fluid from the pump is supplied to the hydraulic motor which functions to drive the digger teeth in reciprocation. The residual second portion of the hydraulic power fluid is directed via the control valves 99 to the several hydraulic cylinders 18, 24 and 52 for operating various portions of the back hoe structure.

In the second position of the two position electrical solenoid valve 102 which this valve attains when the push button control 210 is released, all of the hydraulic power fluid directed through the hydraulic power fluid distribution assembly of the invention is passed to and through the manifold in which the several control valves 99 are located, and thus is ultimately directed to the cylinders 18, 24 and 52. In this position of the valve 102, the digger teeth 90 are not reciprocated, since no hydraulic power fluid is supplied to the hydraulic motor 70. This status of the two position electrical solenoid valve 102 is employed when extremely hard or rocky soils are not encountered, and it is desired to obtain maximum power for the purpose of swiveling or rolling the bucket about its horizontal axis.

To consider in greater detail the path of hydraulic power fluid through the hydraulic power fluid distribution assembly of the invention, the power fluid from the main hydraulic pump is first directed from the hydrau-v lic pump carried on the back hoe vehicle through a suitable conduit to the port 126 in the side face 104d of the adapter block 104. After passing into the bore 118 from the port 126, the power fluid flows upwardly through the bore 128 and through the port 130 in the top face 104a of the adapter block, and enters the two position electrical solenoid valve 102 mounted on top of the adapter block against the top face 104a thereof. Any suitable commercially available two position electrical solenoid valve may be employed, such as that which is manufactured and marketed by the Double A Products Company of Manchester, Michigan.

In the split flow condition of the two position electrical solenoid valve 102, (that is, where it is shifted to the position for proportioning the flow to the hydraulic motor 60 which drives the digger teeth 90 in reciprocation, and to the control valves 99 carried on the operators console and ultimately to the cylinders 18, 24 and 52), power fluid is directed through appropriate internal passageways in the valve 102 so that it is returned through a port in the lower face of this valve to the bore in the top face 104a of the adapter block 104. The power fluid flows from the bore 140 into the bore 122, and from this bore into the bore 142 and through the port 144 in the face l04b of the adapter block 104.

From the port 144,'the power fluid flows through the port 146 and downwardly extending passageway 171 into the bore 172 in the flow divider block 106. From the bore 172, hydraulic power fluid moves into the fluid delivery passageway 174, and its rate of flow and volume throughput in this passageway is selectively adjusted by movement of the adjusting screw 176 into or out of the passageway 174.

Hydraulic fluid from the passageway 174 enters one end of the elongated bore 177 and some of the fluid from the bore 172 also enters the opposite end portion of the elongated bore 177. The fluid in opposite ends of the elongated bore 177 acts upon the metering spool 180 disposed therein so that the metering spool is shifted axially within the elongated bore 177 according to the differential pressure established across the central piston or barrier forming a portion of this spool. The metering spool 180 effectively governs the distribution of the total fluid entering the flow divider block 106 from the port 146 into a constant volume passageway 182 and into a residual volume passageway 184. The construction of the metering spool 180 and the adjusting screw 176 are such that they cooperatively function to always direct a certain predetermined volume of flow to the constant volumepassageway 182. The residual fluid is directed into the residual volume passageway 184.

Power fluid from the passageway 182 enters one end of the elongated bore 185 and from this bore is discharged through the port 192 into a conduit leading to the hydraulic motor 70 for the purpose of supplying power fluid thereto to reciprocate the teeth of the back hoe bucket. The residual volume of power fluid moving through the passageway 184 passes into the opposite end of the elongated bore 185, and from this location passes upwardly through a port 158 formed in the upper side of the flow divider block 106, through the opening 156 in the adapter block 104 and into the bore 152 formed therein. From this location, the residual volume power fluid flows out through the bore 124 and a port 125 in the face 1046' of the adapter block, and into a conduit carrying the power fluid to the control console where the control valves 99 are located. Thus, this residual portion of the hydraulic power fluid is used to operate the hydraulic cylinders 18, 24 and 52 at a time when the constant volume of power fluid is being supplied to the motor 70 for driving the digger teeth 90 in reciprocation.

When the two position electrical solenoid valve 102 is shifted to its second position, power fluid which has been passed upwardly into the solenoid valve from the adapter block 104 is returned to the bore 150 in the adapter block, and from this bore flows through the bore 124 and out of the port 125 into the conduit which leads to, and supplies power fluid to, the control valves 99 located at the operators console. In this status of the two position electrical solenoid valve 102, this fluid flow is the total volume of hydraulic power fluid pumped by the hydraulic power fluid pump. At this time and in this status of the electrical solenoid valve, none of the power fluid can flow downwardly through the bore 152 and through the opening or port 158 in the flow divider block 106, since the metering spool 180 prevents retrograde flow of power fluid from the bore 189 and the passageway 184 back into the bore 172. Thus, in this status of the two position electrical solenoid valve 102, power fluid is only supplied via the bore 124 to the conduit which leads to the control valves 99, so that all of the fluid is ultimately directed to the cylinders 18, M and 52 and is effective for their operation, and no hydraulic power fluid is directed to the motor which drives the digger teeth in reciprocation.

To further assure the supply of a constant volume of power fluid to the motor 70 for operating the digger teeth when the electrical solenoid valve 102 is in the split flow status, a pressure relief valve which includes the spring 194a and ball 194b operating against the check seat 198 is provided within the bore 185. The pressure relief valve thus constituted will open when a pre-selected pressure is exceeded in the power fluid moving through the passageway 182 and out of the port 192. Fluid thus vented past the pressure relief valve when the ball 194b unseats is bled through the bore 185 and the tank port 200, and is returned by a suitable conduit to the hydraulic power fluid reservoir.

Although a preferred embodiment of the invention has been herein illustrated and described, it will be understood that various changes and innovations can be effected in the described embodiment of the invention, including the arrangement of parts and structures in the overall combination, without departure from the basic principles which underlie the invention. Changes and innovations of this type are therefore deemed to be circumscribed by the spirit and scope of the invention, except as the same may be necessarily limited by the ap pended claims or reasonable equivalents thereof.

What is claimed is:

1. In a back hoe excavating apparatus having an articulated boom, a bucket mounted on said boom for pivotation about a horizontal axis, a source of hydraulic power fluid, hydraulic cylinder means for pivoting said bucket and extending said boom, teeth movably mounted on said bucket at the digging edge thereof, control valve means for controlling the flow of hydraulic power fluid to said hydraulic cylinder means, and means for hydraulically driving said teeth in reciprocation, the improvement which comprises: a first port solenoid valve means for receiving hydraulic power fluid through port therein, and for alternately directing said power fluid outwardly through one or the other of two other ports therein when said valve is alternately shifted between two operating positions;

a fluid flow divider block having one intake port and two discharge ports for receiving hydraulic power fluid through said intake port, and discharging said power fluid through one or both of said discharge ports, said flow divider including means for direct ing a constant volume of power fluid through one of said discharge ports, and a residual portion of the hydraulic power fluid received from said intake port through the other of said discharge ports; and

an adapter block having a second planar face on one side thereof, another face extending parallel to said second face on the opposite side thereof, and additional faces extending between said second face and other face, said adapter block being positioned between said solenoid valve means and flow divider block, said adapter block including:

first fluid passageway means for conveying power fluid through said adapter block from a first port in one of said additional faces thereof to a second port in said second face thereof registering with said first port in said solenoid valve means;

second fluid passageway means for conveying power fluid from a third port in said second face of said adapter block through said adapter block to a fourth port in said other face of said adapter block on the opposite side thereof from said second face, which fourth port is in registry with the intake port in said fluid flow divider block; and

third fluid passageway means having a fifth port in said second face of said adapter block and positioned for registry with one of said two other ports in said solenoid valve means, and having a sixth port opening in one of said additional faces of said adapter block for discharging power fluid from said third fluid passageway means, and having a seventh port in said other face of said adapter block and positioned for registry with one of said two discharge ports in said fluid flow divider block;

a first conduit connecting said sixth port forming a portion of said third fluid passageway means with said control valve means for directing hydraulic power fluid to said control valve means;

a second conduit connecting said source of hydraulic power fluid with said first port forming a part of the first fluid passageway means in said adapter block; and

a third conduit connected between one of said discharge ports in said fluid flow divider block and said means for hydraulically driving said teeth in reciprocation, whereby when said solenoid valve is shifted to one of said two operating positions, hydraulic power fluid is directed through said adapter block, solenoid valve and fluid flow divider block solely to said control valve means, and when said solenoid valve means is shifted to the other of said two operating positions, hydraulic power fluid is directed in a predetermined constant volume to said means for hydraulically driving said teeth in reciprocation, and the remainder of hydraulic power fluid which is supplied to said flow divider block through said one intake port is directed to said control valve means via said adapter block, solenoid valve and fluid flow divider block.

2. The improvement defined in claim 1 wherein said fluid flow divider block includes an adjusting screw positioned between said intake port and said two discharge ports for selectively adjusting the constant volume from the total flow entering the intake port which is ultimately discharged from one of the two discharge ports in said fluid flow divider block.

3. The improvement defined in claim 1 and further characterized as including a metering spool for preventing fluid flow toward the intake port of said fluid flow divider block from the discharge port thereof which registers with said seventh port in said adapter block.

4. In combination, a self-powered vehicle, an articulated boom mounted on the vehicle, a digger bucket pivotally carried on the end of the boom remote from the bucket for pivotation about a horizontal axis, first hydraulic power means for articulating the boom, second hydraulic means for pivoting the bucket about said horizontal axis, digger teeth mounted on said bucket, third hydraulic power means for cyclically moving said digger teeth, a source of hydraulic power fluid, a control valve assembly including control valves for controlling the flow of hydraulic power fluid to said first and second hydraulic power means, and a power fluid distribution assembly for distributing power fluid in preselected portions to said control valves and said third hydraulic power means, said power fluid distribution assembly comprising:

valve means for directing hydraulic power fluid through a first discharge port, aor alternately, through a second discharge port; and fluid distributing and proportioning means connected to said valve means, and having a plurality of bores therein for receiving power fluid from said valve means, said fluid distributing and proportioning means including a first discharge port adapted for connection through a conduit to said control valves, and a second discharge port adapted for connection through a conduit to said third hydraulic power means, said bores being disposed in said fluid distributing and proportioning means for, at one time and during one status of said valve means, receiving hydraulic fluid from said first discharge port in said valve means and discharging the power fluid so received through said first discharge port of said fluid distributing and proportioning means to said control valves, and, at a different time and during a different status of said valve means, receiving hydraulic power fluid from said second discharge port of said valve means and directing said power fluid through said second discharge port of said fluid distributing and proportioning means, and concurrently through said first discharge port of said fluid distributing and proportioning means for directing hydraulic power fluid to said control valves, and concurrently in a constant, pre-selected volume, to said third hydraulic power means. 5. The combination defined in claim 4 wherein said fluid distributing and proportioning means comprises:

to said flow divider block.

-, P0 1050 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION mum; No. 3,828,951 Dated August 13, 1974 Inventor) Ancel H. Fleming It is certified that error appears in the above-identified patentond that said Letters Patent are hereby corrected as shown below:

Claim 1 (Col. 10, line 42) where after the word "comprises", the words -a first porthave been erroneously inserted and should be deleted.

Col. 10, line 44, after the word "through" and before the word "port",.the words a first-- should be inserted.

Col. 12, line 31, the word "power" should be inserted after the word "hydraulic".

Col. 12, line 17, "aor should be changed'to -or--.

Signed and sealed this 29th day of October 1974.

. (SEAL) Attest: McCOY M. GIBSON JR. c. MARSHALL DANN Attestin'g Officer Commissioner of Patents 

1. In a back hoe excavating apparatus having an articulated boom, a bucket mounted on said boom for pivotation about a horizontal axis, a source of hydraulic power fluid, hydraulic cylinder means for pivoting said bucket and extending said boom, teeth movably mounted on said bucket at the digging edge thereof, control valve means for controlling the flow of hydraulic power fluid to said hydraulic cylinder means, and means for hydraulically driving said teeth in reciprocation, the improvement which comprises: a first port solenoid valve means for receiving hydraulic power fluid through port therein, and for alternately directing said power fluid outwardly through one or the other of two other ports therein when said valve is alternately shifted between two operating positions; a fluid flow divider block having one intake port and two discharge ports for receiving hydraulic power fluid through said intake port, and discharging said power fluid through one or both of said discharge ports, said flow divider including means for directing a constant volume of power fluid through one of said discharge ports, and a residual portion of the hydraulic power fluid received from said intake port through the other of said discharge ports; and an adapter block having a second planar face on one side thereof, another face extending parallel to said second face on the opposite side thereof, and additional faces extending between said second face and other face, said adapter block being positioned between said solenoid valve means and flow divider block, said adapter block including: first fluid passageway means for conveying power fluid through said adapter block from a first port in one of said additional faces thereof to a second port in said second face thereof registering with said first port in said solenoid valve means; second fluid passageway means for conveying power fluid from a third port in said second face of said adapter block through said adapter block to a fourth port in said other face of said adapter bloCk on the opposite side thereof from said second face, which fourth port is in registry with the intake port in said fluid flow divider block; and third fluid passageway means having a fifth port in said second face of said adapter block and positioned for registry with one of said two other ports in said solenoid valve means, and having a sixth port opening in one of said additional faces of said adapter block for discharging power fluid from said third fluid passageway means, and having a seventh port in said other face of said adapter block and positioned for registry with one of said two discharge ports in said fluid flow divider block; a first conduit connecting said sixth port forming a portion of said third fluid passageway means with said control valve means for directing hydraulic power fluid to said control valve means; a second conduit connecting said source of hydraulic power fluid with said first port forming a part of the first fluid passageway means in said adapter block; and a third conduit connected between one of said discharge ports in said fluid flow divider block and said means for hydraulically driving said teeth in reciprocation, whereby when said solenoid valve is shifted to one of said two operating positions, hydraulic power fluid is directed through said adapter block, solenoid valve and fluid flow divider block solely to said control valve means, and when said solenoid valve means is shifted to the other of said two operating positions, hydraulic power fluid is directed in a predetermined constant volume to said means for hydraulically driving said teeth in reciprocation, and the remainder of hydraulic power fluid which is supplied to said flow divider block through said one intake port is directed to said control valve means via said adapter block, solenoid valve and fluid flow divider block.
 2. The improvement defined in claim 1 wherein said fluid flow divider block includes an adjusting screw positioned between said intake port and said two discharge ports for selectively adjusting the constant volume from the total flow entering the intake port which is ultimately discharged from one of the two discharge ports in said fluid flow divider block.
 3. The improvement defined in claim 1 and further characterized as including a metering spool for preventing fluid flow toward the intake port of said fluid flow divider block from the discharge port thereof which registers with said seventh port in said adapter block.
 4. In combination, a self-powered vehicle, an articulated boom mounted on the vehicle, a digger bucket pivotally carried on the end of the boom remote from the bucket for pivotation about a horizontal axis, first hydraulic power means for articulating the boom, second hydraulic means for pivoting the bucket about said horizontal axis, digger teeth mounted on said bucket, third hydraulic power means for cyclically moving said digger teeth, a source of hydraulic power fluid, a control valve assembly including control valves for controlling the flow of hydraulic power fluid to said first and second hydraulic power means, and a power fluid distribution assembly for distributing power fluid in pre-selected portions to said control valves and said third hydraulic power means, said power fluid distribution assembly comprising: valve means for directing hydraulic power fluid through a first discharge port, aor alternately, through a second discharge port; and fluid distributing and proportioning means connected to said valve means, and having a plurality of bores therein for receiving power fluid from said valve means, said fluid distributing and proportioning means including a first discharge port adapted for connection through a conduit to said control valves, and a second discharge port adapted for connection through a conduit to said third hydraulic power means, said bores being disposed in said fluid distributing and proportioning means for, at one time and during one status of said valve means, rEceiving hydraulic fluid from said first discharge port in said valve means and discharging the power fluid so received through said first discharge port of said fluid distributing and proportioning means to said control valves, and, at a different time and during a different status of said valve means, receiving hydraulic power fluid from said second discharge port of said valve means and directing said power fluid through said second discharge port of said fluid distributing and proportioning means, and concurrently through said first discharge port of said fluid distributing and proportioning means for directing hydraulic power fluid to said control valves, and concurrently in a constant, pre-selected volume, to said third hydraulic power means.
 5. The combination defined in claim 4 wherein said fluid distributing and proportioning means comprises: A fluid flow divider block for proportionately dividing hydraulic power fluid charged thereto into a plurality of streams of power fluid discharged therefrom; and an adapter block positioned between said valve means and said fluid flow divider block for selectively directing the input and discharge of hydraulic power fluid to and from said valve means, and to said flow divider block. 